Fair Value Disclosures - Carrying and Fair Values of Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
4.50% Notes [Member]
Notes, mortgage notes and other debt [Abstract]
Stated interest rate (percent)	4.50%	4.50%
7.50% Notes [Member]
Notes, mortgage notes and other debt [Abstract]
Stated interest rate (percent)	7.50%	7.50%
7.5% Senior Exchange Convertible Notes [Member]
Notes, mortgage notes and other debt [Abstract]
Stated interest rate (percent)	7.50%	7.50%
Carrying Amount [Member] | 4.50% Notes [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notes Payable, Fair Value Disclosure	$ 5,402	$ 5,402
Carrying Amount [Member] | Notes and Senior Exchange Convertible Notes [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notes Payable, Fair Value Disclosure	99,981	100,000
Estimate of Fair Value, Fair Value Disclosure [Member] | 4.50% Notes [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notes Payable, Fair Value Disclosure	5,402	5,425
Estimate of Fair Value, Fair Value Disclosure [Member] | Notes and Senior Exchange Convertible Notes [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notes Payable, Fair Value Disclosure	$ 110,938	$ 111,775